Field of the Invention
The present invention relates to a sensing device, and in particular, to a physiology signal sensing device.
Description of the Related Art
In general, conventional mechanical blood pressure monitors have pumping cuffs to apply pressure on users. However, the pressure generated by the pumping cuff is not comfortable for users, and thus, the blood pressure monitors may not be continually used for a long time. Moreover, the blood pressure monitors are not be carried easily by a user because of the large size and the heavy weight of the pumping cuff.
Otherwise, an electronic type of conventional blood pressure monitors is available, which utilizes piezoelectric sensors for detecting. The piezoelectric sensors have the advantage of being small size, and continually used for a long time is available. However, the cost of the piezoelectric sensor is high, and the blood pressure detected by the blood pressure monitor is not accurate because the current generated by the piezoelectric sensor is unstable. Thus, the piezoelectric sensor is usually used for detecting heart rates only.